The grid is specified in terms of triangular prisms and facilitates representation of complex geometries and highly-variable spatial discretization, which is particularly useful for mining applications with complex geologic structures and steep hydraulic gradients.
The elevation of nodes of the finite-element grid can be defined to vary through time. This enables more accurate representation of the underground workings and open pits according to the mine schedules being evaluated.
The finite-element grid can remain fixed through time (with the exception of excavations), and the saturated flow domain can change through time in accordance with changes in the water table, further facilitating representation of the spatial hydrogeologic variability of the groundwater system without additional computational overhead of solving unsaturated flow equations.
Represent geology, model domain, pit geometry, groundwater heads, and pore pressures in 3-D.
Flexible Boundary Conditions
Boundary conditions can be represented as specified-head, specified-flux, and internal source-sink terms (each of which can be variant or invariant with time), or as variable-flux boundaries
that simulate time-variant fluxes in response to changing boundary heads and an infinite aquifer.
Very Transmissive Zones
By defining links between specific node pairs with enhanced conductivity, very transmissive zones can be used to accurately represent tunnels, underground workings, declines, conductive faults, wells pumping from multiple layers, etc.
Streams are simulated as river networks of hydraulic compartmentalization and the model simulates river depletions and additions from exchange with groundwater.
Loss of water from bare/vegetated soils can be simulated and is proportional to the distance between the ground surface and water table, with maximum evaporation rate and extinction depth as constraints.
Excavation and pit-lake infilling of multiple pits can be simulated within the same model domain and their respective mining schedules represented simultaneously. The model also provides node-by-node fluxes into/out of the pit lake, evaporation and precipitation on the lake surface, and predictions of lake stages as a function of time, which can readily be used to predict detailed hydrodynamic and geochemical pit-lake conditions and to predict pit-wall seepage during mining.
Can be used to represent the zone of relaxation around excavations, backfilling operations, longwall and room-and-pillar coal mining, freeze-thaw conditions, or other scenarios where hydraulic conductivity may change during the simulation period.
Due in part to the finite element grid and the numerical methods applied in the model, MINEDW is typically very stable numerically. This is particularly important in cases where there is a high degree of hydraulic compartmentalization with steep hydraulic gradients.